Flexible slot architecture for low latency communication

ABSTRACT

Systems and methods are disclosed in which the start time of a downlink transmission to a user equipment (UE) is more flexible. For example, instead of beginning at predetermined starting points in a frame or subframe, a downlink transmission may instead possibly begin every x OFDM symbols, where x may be as small as one OFDM symbol.

RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 15/709,018, which was filed on Sep. 19, 2017, and titled“Flexible Slot Architecture For Low Latency Communication”, which claimsthe benefit of U.S. Provisional Patent Application Ser. No. 62/398,320,entitled “Flexible Slot Architecture for Low Latency Communication”,which was filed on Sep. 22, 2016.

U.S. patent application Ser. No. 15/709,018 and U.S. Provisional PatentApplication Ser. No. 62/398,320 are both incorporated herein byreference.

FIELD

The present application relates to wireless communications, and moreparticularly to low latency communication.

BACKGROUND

In some wireless communication systems, user equipments (UEs) wirelesslycommunicate with one or more base stations. The wireless communicationsmay be performed by transmitting orthogonal frequency-divisionmultiplexing (OFDM) symbols, which may be transmitted according to anorthogonal multiple access scheme such as orthogonal frequency-divisionmultiple access (OFDMA), or a non-orthogonal multiple access (NoMA)scheme such as sparse code multiple access (SCMA).

A wireless communication from a UE to a base station is referred to asan uplink communication. A wireless communication from a base station toa UE is referred to as a downlink communication. Resources are requiredto perform uplink and downlink communications. For example, a basestation may wirelessly transmit data to a UE in a downlink communicationat a particular frequency for a particular duration of time. Thefrequency and time duration are examples of resources.

Some UEs served by a base station may need to receive data from the basestation and/or transmit data to the base station with low latency, forexample by keeping (uplink and/or downlink) transmissions within 0.5 msor the overall end-to-end (or return) latency within 1 ms. For example,a base station may serve multiple UEs, including a first UE and a secondUE. The first UE may be a mobile device carried by a human who is usingthe first UE to browse on the Internet. The second UE may be equipmenton an autonomous vehicle driving on a highway. Although the base stationis serving both UEs, the second UE may need to send and/or receive datawith lower latency compared to the first UE. The second UE may also needto send and/or receive its data with high reliability. The second UE maybe an ultra-reliable low latency communication (URLLC) UE, whereas thefirst UE may be an enhanced mobile broadband (eMBB) UE.

UEs that are served by a base station and that require lower latencycommunication will be referred to as “low latency UEs”. The other UEsserved by the base station will be referred to as “latency tolerantUEs”. Data to be transmitted between a base station and a low latency UEwill be referred to as “low latency data”, and data to be transmittedbetween a base station and a latency tolerant UE will be referred to as“latency tolerant data”. It is contemplated that a single UE might useboth low latency communication and latency tolerant communication, inwhich case the term “low latency UE” would refer to the activities ofthe single UE for the purpose of low latency communication and the term“latency tolerant UE” would refer to the activities of the single UE forthe purpose of latency tolerant communication.

It is desired to accommodate the presence of both low latency andlatency tolerant communications in shared time-frequency resources toimprove resource utilization.

SUMMARY

Low latency data may be bursty or sporadic in nature, and may betransmitted in short packets. A transmission to/from a low latency UEmay take place during a time slot which may occupy a small number ofOFDM symbols (e.g., 7 OFDM symbols), and a subframe for wirelesscommunication may be subdivided into slots. If low latency data arrivesfor transmission in the middle of a slot, it is required to wait untilthe start of the next slot before transmitting the low latency data, andlatency is introduced during the waiting. Systems and methods aredisclosed in which the start time of a low latency transmission is moreflexible.

Systems and methods are also disclosed in which the start time of adownlink transmission to a UE is more flexible. For example, instead ofbeginning at predetermined starting points in a frame or subframe, adownlink transmission may instead possibly begin every x OFDM symbols,where x may be as small as one OFDM symbol. A UE is therefore configuredto monitor for control information on a periodic basis, where thecontrol information indicates a downlink transmission for the UE (e.g.the control information may be a downlink grant). The UE may beconfigured to monitor for the control information once every x OFDMsymbols.

In one embodiment, there is provided a method performed by a UE. Themethod includes receiving configuration signaling. The configurationsignaling indicates a plurality of start locations. Each start locationoccurs x OFDM symbols apart from an adjacent start location. The methodmay further include, for each one of at least some of the plurality ofstart locations, the UE monitoring for control information at that startlocation. The control information indicates that a downlink datatransmission for the UE has been scheduled during a particular timeinterval that begins at that start location. The method may furtherinclude, for one of the at least some of the plurality of startlocations, receiving the control information and the downlink datatransmission during the particular time interval.

In another embodiment, there is provided a method performed by a basestation. The method includes the base station transmitting, to a UE,configuration signaling. The configuration signaling indicates aplurality of start locations, each of which the UE is to monitor forcontrol information. Each start location occurs x OFDM symbols apartfrom an adjacent start location. The method may further include the basestation transmitting control information at a particular start locationof the plurality of start locations. The control information indicatesthat a downlink data transmission for the UE has been scheduled during atime interval that begins at the particular start location. The methodmay further include the base station transmitting the downlink datatransmission during the time interval.

UEs and base stations configured to perform the methods disclosed hereinare also provided.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will be described, by way of example only, with reference tothe accompanying figures wherein:

FIG. 1 is a block diagram of a base station and four UEs, according toone embodiment;

FIG. 2 is a block diagram showing an example of a base station and a UE;

FIGS. 3 to 12 each illustrate time/frequency resources in more detailand show the coexistence of low latency and latency tolerantcommunications;

FIGS. 13 to 17 are methods according to various embodiments;

FIG. 18 illustrates an example communication system in which embodimentsof the present disclosure could be implemented;

FIG. 19 illustrates two neighboring new radio (NR) cells of an examplecommunication system in which embodiments of the present disclosurecould be implemented; and

FIGS. 20 and 21 illustrate example devices that may implement themethods and teachings according to this disclosure.

DETAILED DESCRIPTION

For illustrative purposes, specific example embodiments will now beexplained in greater detail below in conjunction with the figures.

FIG. 1 is a block diagram of a base station 100, as well as four UEs 102a, 102 b, 104 a, and 104 b served by the base station 100, according toone embodiment. UEs 102 a and 102 b are low latency UEs, and UEs 104 aand 104 b are latency tolerant UEs. That is, UEs 102 a and 102 b requirelower latency uplink and/or downlink communication compared to UEs 104 aand 104 b. For example, UEs 102 a and 102 b may be URLLC UEs, and UEs104 a and 104 b may be eMBB UEs. Although the base station 100 onlyserves four UEs in FIG. 1, in actual operation the base station 100 mayserve many more UEs. In examples described herein, downlinktransmissions to the low latency UEs are grant-based and uplinktransmissions from the low latency UEs are grant-free. However, moregenerally uplink and/or downlink transmissions between the base stationand low latency UEs may be grant-based and/or grant-free.

The base station 100 includes one or more antennas 122 to wirelesslytransmit signals carrying data for UEs 102 a, 102 b, 104 a, and 104 b,and to wirelessly receive signals carrying data from UEs 102 a, 102 b,104 a, and 104 b. Only one antenna 122 is illustrated. The base station100 includes other circuitry and modules, but these have been omittedfor the sake of clarity. For example, the base station 100 may include aprocessor (not shown) that executes instructions stored in a memory (notshown). When the instructions are executed, the processor causes thebase station to perform the base station operations described belowrelating to downlink scheduling and/or allocation of resources.Alternatively, instead of a processor, the base station operationsdescribed below may be implemented using dedicated integrated circuitry,such as an application specific integrated circuit (ASIC), a graphicsprocessing unit (GPU), or a programmed field programmable gate array(FPGA).

The word “base station” encompasses any device that wirelesslycommunicates with UEs using uplink and/or downlink communications.Therefore, in some implementations, the base station 100 may be calledother names, such as a base transceiver station, a radio base station, anetwork node, an access point, a transmit node, a Node B, an evolvedNode B (eNodeB), a relay station, a remote radio head, a transmit point,or a transmit and receive point. Also, in some embodiments, thecomponents of the base station 100 are distributed. For example, somecomponents of the base station 100 may be coupled to equipment housingthe antennas 122 over a communication link (not illustrated). Therefore,in some embodiments, the term base station 100 may also refer to moduleson the network side that perform operations, such as resourceallocation, control information generation, and message generation, andthat are not necessarily part of the equipment housing the antennas 122of the base station 100. Although only a single base station is shown,it is contemplated that there may be more than one base station usingsynchronized communications to implement embodiments disclosed herein.

When a wireless transmission between the base station 100 and one ormore of UEs 102 a, 102 b, 104 a, and/or 104 b occurs, the transmissionuses allocated resources, for example time/frequency resources. Anexample of time/frequency resources is indicated at 126. Examplespecific resource partitions allocated to UEs are shown at 118 and 120.

A region 128 of the time/frequency resources 126 is reserved or used forthe transmission of latency tolerant data, and this region 128 will bereferred to as the latency tolerant region. Another region 130 of thetime/frequency resources 126 is reserved or used for the transmission ofboth latency tolerant data and low latency data, and this region 130will be referred to as the co-existence region. Region 128 isillustrated as a separate frequency range from region 130, although ingeneral this need not be the case. Also, there may be another region(not shown) that is reserved just for the transmission of low latencydata. Other types of regions may additionally or alternatively bepresent, such as other regions for coexistence of low latency andlatency tolerant data. For example, the time/frequency resources couldbe partitioned into a low latency region and a coexistence region, orinto a latency tolerant region and a coexistence region. It is alsocontemplated that the partitioning of the time/frequency resources couldbe time division multiplexing (TDM) based, frequency divisionmultiplexing (FDM) based, or in any other suitable manner, and that thepartitions may change dynamically or semi-statically over time.

The resources used for low latency communications may be partitionedinto time intervals called slots. A slot used for low latencycommunication can be referred to as a “low latency slot” or a “minislot”. A slot may be defined as a particular number of OFDM symbols,e.g. 7 or 14 OFDM symbols in some embodiments. An example of a lowlatency slot duration is shown at 142. A low latency slot carries anencoded transport block to or from a low latency UE. It is contemplatedthat in some cases, an encoded transport block may span more than oneslot. A low latency slot encompasses a particular number of OFDMsymbols, e.g. 7 OFDM symbols or any other integer number of OFDMsymbols. A low latency slot may be equal to, more than, or less than asubframe duration, depending upon the implementation. A low latency slotduration may be equal to one transmission time unit (TTU), or encompassmultiple TTUs, depending upon the implementation. Therefore, although“low latency slot” is used herein, it may be interchangeably called a“low latency subframe” in implementations in which a low latency slothas the same duration as a subframe. Also, “low latency slot” may beinterchangeably called a “low latency TTU” in implementations in which alow latency slot has the same duration as a TTU. Also, a TTU issometimes referred to as a transmission time interval (TTI). It iscontemplated that latency tolerant traffic may optionally use the sameslot duration as low latency traffic.

The resources used for latency tolerant communications may bepartitioned into intervals. An interval used for latency tolerantcommunication will be referred to as a “latency tolerant interval”. Anexample of a latency tolerant interval is shown at 144. A latencytolerant interval is the smallest interval of time that may be scheduledor allocated for a data transmission to/from a latency tolerant UE.

As shown in FIG. 1, a low latency slot has a time duration that isshorter than a latency tolerant interval. By transmitting low latencyslots of a shorter duration, the latency of the data transmissionsto/from the low latency UEs may be reduced.

Each one of UEs 102 a, 102 b, 104 a, and 104 b includes one or moreantennas for wirelessly transmitting data to the base station 100 andwirelessly receiving data from the base station. Only one antenna isillustrated on each UE. Each UE would also include other circuitry andmodules, but these have been omitted for the sake of clarity. Forexample, a UE may include a processor (not shown) that executesinstructions stored in a memory (not shown). When the instructions areexecuted, the processor causes the UE to perform the UE operationsdescribed below relating to scheduling and/or allocating of resourcesand/or processing control information and monitoring configurationinformation. Alternatively, instead of a processor, the UE operationsdescribed below may be implemented using dedicated integrated circuitry,such as an ASIC, a GPU, or an FPGA.

FIG. 2 is a block diagram showing an example of the base station 100 andan example of a UE of FIG. 1 in more detail. The UE may be UE 102 a, 102b, 104 a, or 104 b.

The base station 100 includes a transmitter 164 and a receiver 166coupled to one or more antennas 122. Only one antenna 122 isillustrated. The transmitter 164 and the receiver 166 may be integratedas a transceiver. The transmitter 164 may implement some or all of thedownlink physical layer operations of the base station 100, and thereceiver 166 may implement some or all of the uplink physical layeroperations of the base station 100. The base station 100 furtherincludes a message processor 170 for processing uplink transmissionsfrom the UEs. The message processor 170 may be part of the receiver 166.The message processor 170 may include a decoder (not shown) for decodinguplink transmissions from the UEs. The base station 100 further includesa resource allocator 168, which may perform operations such as:generating scheduling grants; and/or partitioning the resources intocoexistence, latency tolerant only, and/or low latency only regions;and/or configuring subcarrier spacing; and/orpuncturing/postponing/withholding latency tolerant data transmissions toUEs 104 a or 104 b; and/or allocating a flexible slot start time for lowlatency data in the manner discussed herein.

The base station further 100 includes a control information generator169 that generates, among other things, the following information:

(1) The monitoring configuration information, which indicates to a UE aplurality of start locations (OFDM symbols) at which the UE is tomonitor for control information. The monitoring configurationinformation may indicate periodic monitoring, e.g. the UE is to monitorfor the control information once every x OFDM symbols.(2) The control information for which the UE monitors. The controlinformation indicates a downlink data transmission for the UE. If a UEsupports uplink (“UL”) grant-based transmission, the UE may also monitorcontrol information in the downlink (“DL”) to receive the UL grant,which assigns resources for the UL data transmission.

The monitoring configuration information and control information thatare generated by the control information generator 169 are sent to theUE via the transmitter 164.

The message processor 170, the resource allocator 168, the controlinformation generator 169, and/or any signal processing components ofthe transmitter 164 and receiver 166, may be implemented in the form ofcircuitry configured to perform the functions of the message processor170, the resource allocator 168, the control information generator 169,and/or the transmitter 164/receiver 166. In some implementations thecircuitry includes a memory and one or more processors that executeinstructions stored in the memory that cause the one or more processorsto perform the operations of the message processor 170, the resourceallocator 168, the control information generator 169, and/or thetransmitter 164/receiver 166. Alternatively, the message processor 170,the resource allocator 168, the control information generator 169,and/or any signal processing components of the transmitter 164 andreceiver 166, may be implemented using dedicated circuitry, such as anASIC, a GPU, or a programmed FPGA for performing the operations of themessage processor 170, the resource allocator 168, the controlinformation generator 169, and/or the transmitter 164/receiver 166. Inyet other implementations, the functionality of the base station 100described herein may be fully or partially implemented in software ormodules stored in the memory and executed by the one or more processors.

The UE illustrated in FIG. 2 also includes a transmitter 174 and areceiver 176 coupled to one or more antennas 162. Only one antenna 162is illustrated. The transmitter 174 and the receiver 176 may beintegrated as a transceiver. The transmitter 174 may implement some orall of the uplink physical layer operations of the UE, and the receiver176 may implement some or all of the downlink physical layer operationsof the UE. The UE further includes a message processor 178 forgenerating messages to be transmitted in grant-based and/or grant-freeuplink transmissions, and for processing received messages. Generatingan uplink message may include encoding and modulating the data to betransmitted in the message. Processing a received message may includedecoding and demodulating the data received in the downlink transmissionmessage. For example, the message processor 178 may include a decoder(not shown) for decoding a downlink transmission from the base station100. In some embodiments, the message processor 178 processes updateinformation present in the downlink transmission (e.g. in the form of anindicator) in order to determine if there is particular data (e.g.punctured data or withheld data) in the downlink transmission messagethat is to be removed from decoding.

The UE further includes a control information processor 179 forprocessing the monitoring configuration indication received from thebase station 100, and for causing the UE to monitor for the controlinformation according to the monitoring configuration indication. Themonitoring configuration indication is signaling. The controlinformation processor 179 also processes the control informationreceived when monitoring, e.g. to determine if there is a downlinktransmission for the UE.

The message processor 178, control information processor 179, and/or anysignal processing components of the transmitter 174 and receiver 176,may be implemented in the form of circuitry configured to perform thefunctions of the message processor 178, the control informationprocessor 179, the transmitter 174 and/or receiver 176. In someimplementations the circuitry includes a memory and one or moreprocessors that execute instructions stored in the memory that cause theone or more processors to perform the operations of the messageprocessor 178, the control information processor 179, and/or thetransmitter 174/receiver 176. Alternatively, message processor 178, thecontrol information processor 179, and/or any signal processingcomponents of the transmitter 174 and receiver 176, may be implementedusing dedicated circuitry, such as an ASIC, a GPU, or an FPGA forperforming the operations of the message processor 178, the controlinformation processor 179, and/or the transmitter 174/receiver 176. Inyet other implementations, the functionality of the UE described hereinmay be fully or partially implemented in software or modules stored inthe memory and executed by the one or more processors.

Low latency data may be bursty or sporadic in nature, and may betransmitted in short packets. A transmission to/from a low latency UEtakes place during a slot, and traditionally one slot starts afteranother. If low latency data arrives for transmission in the middle of alow latency slot duration, and it is required to wait until the start ofthe next low latency slot before transmitting the low latency data, thenlatency is introduced. The latency occurs regardless of whether thetransmission is grant-free or grant-based.

Systems and methods are disclosed in which the start time of a lowlatency slot in the co-existence region 130, or in any region containinglow latency traffic, is more flexible. For example, FIG. 3 illustratesthe co-existence region 130 in more detail. Instead of a low latencyslot only beginning at predetermined starting point A, B, C, or D, aslot may instead begin every x OFDM symbols, that is each start locationoccurs x OFDM symbols apart from an adjacent start location. x can be assmall as one OFDM symbol. In FIG. 3, x is the duration of one OFDMsymbol, but this is only an example. In FIG. 3, subsequentpre-determined starting positions have an interval of 5x OFDM symbols.In some embodiments, x may instead be measured in time, e.g. xmilliseconds, corresponding to an integer number of OFDM symbols in apredetermined numerology. This implies that transmission of a UE can beconfigured to start every x ms regardless of numerology, and x ms maycomprise a different number of symbols in different numerologies. Forexample, if x is 0.5 ms, then it corresponds to 7 symbols based on 15kHz subcarrier spacing, 14 symbols based on 30 kHz subcarrier spacing,and 28 symbols based on 60 kHz subcarrier spacing for normal CPoverhead. Hence, in number of symbols, the periodicity of potentialstarting positions can be scalable.

In FIG. 3, the low latency slot durations are still fixed, but the slotstart time is configurable and therefore more flexible. In someembodiments, low latency slots allocated to different UEs may co-existand possibly use overlapping resources. Different UEs may have differentlow latency slot durations. Also, even though embodiments are presentedwith respect to a time-frequency region where both low latency andlatency tolerant transmissions may coexist, the principles discussedherein regarding flexible starting position can be applicable to anytime-frequency region where there is benefit to have this flexibility.Moreover, the principle of flexible starting position can be applicableto both TDD and FDD systems, as shown in examples and embodiments below.

More generally, and still with reference to FIG. 3, a particular timeinterval may have N OFDM symbols, and a low latency transmission mayhave a duration of k<N OFDM symbols. The low latency transmission mayadvantageously begin at any one of m>N/k possible OFDM symbol locationswithin the time interval. Note that this is only an example. Asdiscussed above, the low latency transmission may be configured to beginevery x OFDM symbols within a time interval for a given numerology.

Some more specific example embodiments will now be described. Thetime/frequency resources described below may be part of thetime/frequency resources 126.

FIG. 4 illustrates a portion of time/frequency resources 202, accordingto one embodiment. The blocks labelled “D” are downlink OFDM symbols,the blocks labelled “U” are uplink OFDM symbols, and the blocks labelled“GP” are OFDM symbol durations used as a guard period during which thereis no data transmission. The notation “D”, “U”, and “GP” will also beused in other figures. However, in all embodiments described withreference to uplink and downlink symbols in the same time intervalseparated by a guard period, it should be understood that the embodimentcan apply equally to time intervals that are uplink only, or downlinkonly, as applicable. In these examples, a slot may include multiplesymbols irrespective of whether they occur within a common latencytolerant interval, or whether they coexist with latency toleranttraffic. Note also that a latency tolerant interval may be any intervalthat is longer than the duration of a low latency transmission.

A duration in time equal to one latency tolerant interval is illustratedin FIG. 4. The illustrated time interval is “downlink dominated” becauseit includes more downlink OFDM symbols than uplink OFDM symbols. Also,the time interval may be referred to as a “self-contained time divisionduplex (TDD) time interval” because there are both downlink and uplinkOFDM symbols. The portion of time/frequency resources 202 illustratedmay be referred to as having a self-contained TDD time interval equal tothe latency tolerant interval. More generally, the interval consists ofat least one DL to UL switching point.

In FIG. 4, there are three downlink low latency slots 204, 206, and 208,for transmitting low latency data. As an example, if the base station100 has low latency data to send to low latency UE 102 a, then the basestation 100 may schedule the low latency data in downlink low latencyslot 204. However, if during low latency slot 204, low latency data forlow latency UE 102 b arrives at the base station 100, then the basestation 100 needs to wait until the start of the second low latency slot206 to transmit the data to low latency UE 102 b. Waiting until thestart of the second low latency slot 206 may introduce an unacceptableamount of latency. In this example, the DL transmission can only beginat some pre-fixed locations within the interval comprising DL symbols.Other slot configurations are possible. A slot may contain symbols thatare not contiguous in time, for example a slot may include one or morefinal downlink symbols in one latency tolerant interval and one or moreinitial downlink symbols in the following latency tolerant interval.This implies that a low latency transmission may comprise OFDM symbolsthat are not contiguous in time. This is due to the fact that some OFDMsymbols may be unknown or reserved from a UE perspective, which may notbe used for transmission and/or reception of control and/or data. A lowlatency transmission can be made avoiding such symbols.

FIG. 5 illustrates a portion of time/frequency resources 222, accordingto another embodiment in which there is flexibility in where low latencyslots may begin. In FIG. 5, a low latency downlink slot may begin at anyone of the first eight downlink OFDM symbols, as shown at 224. The startlocation of a low latency slot can be flexible to try to reduce orminimize access delay. In this example, x is 1 OFDM symbol. In theembodiment of FIG. 5, the duration of a low latency slot is three OFDMsymbols, which is why a low latency slot cannot start at the beginningof the last two downlink OFDM symbols. Alternatively, some UEs mayreceive transmission in the last few DL symbols if they supportnon-contiguous transmission, as mentioned above. However, if the latencytolerant interval contains only downlink symbols, it is contemplatedthat a low latency slot may start at the beginning of any symbol. Usingthe “N” and “k” notation of FIG. 2, in the example in FIG. 5: N=10, k=3,and the start of the low latency slot may begin at any one of the firstm=N−k+1=8 downlink OFDM symbols.

A low latency slot duration of three OFDM symbols is only an example.The number of OFDM symbols in a low latency slot may be more or less.Similarly, the number of OFDM symbols in a latency tolerant interval,including the number of downlink OFDM symbols, the number of uplink OFDMsymbols, and/or the duration of the guard period, may be different fromthe illustrated embodiments. Also, the format and location of thecontrol information for the low latency UEs is implementation specific.In one embodiment, at the start of each of the first eight downlink OFDMsymbols, each low latency UE that is not in the process of receiving adownlink low latency data transmission monitors control information todetermine whether a downlink low latency data transmission to the lowlatency UE will begin at that OFDM symbol. This example implies thatsome UEs can be configured to monitor control information every symbol(i.e., x=1 OFDM symbol) and in some cases, UEs may be configured to skipsome monitoring occasions if they are receiving data.

FIG. 6 is the embodiment of FIG. 5 showing an example in which a lowlatency slot for low latency UE 102 a is scheduled on resources 252, anda low latency slot for low latency UE 102 b is scheduled on resources254. Note that duration of three OFDM symbols is only an example and inpractice, durations of 252 and 254 can be different and any number ofsymbols. In this example, there is more low latency data to send to UE102 b compared to UE 102 a, which is why the amount of frequencyresources allocated to UE 102 b is greater than the amount of frequencyresources allocated to UE 102 a. In FIG. 6, low latency slots cannotoverlap. If the low latency data for UE 102 b had arrived earlier, e.g.at the third downlink OFDM symbol 253, the low latency data for UE 102 bcould not have begun being transmitted until at least the fifth downlinkOFDM symbol 255.

FIG. 7 is the embodiment of FIG. 5 showing an example in which a firstlow latency slot for low latency UE 102 a is scheduled on resources 262,a first low latency slot for low latency UE 102 b is scheduled onresources 264, a second low latency slot for low latency UE 102 a isscheduled on resources 266, and a second low latency slot for lowlatency UE 102 b is scheduled on resources 268. Note that duration ofthree OFDM symbols is only an example and in practice, durations of 262,264, 266, and 268 can be different and any number of symbols. This doesnot change the principle of flexibility of starting position.Alternatively, the low latency slots may be for four different lowlatency UEs. As shown in FIG. 7, low latency slots for different lowlatency UEs overlap in time, but may be mapped to orthogonal ornon-orthogonal resources, for example in the frequency domain.

As is clear from FIGS. 6 and 7, multiple low latency slots can coexistin one latency tolerant interval, and the start location of each lowlatency slot can be configurable and therefore flexible to try to reduceor minimize access delay. Low latency slots for the low latencycommunications are assigned as low latency data arrives at the basestation. A possible benefit of FIG. 6 compared to FIG. 7 is that by notoverlapping low latency slots, there may potentially be lessinterference. Also, a low latency UE in the FIG. 6 embodiment would onlyneed to monitor control information to determine whether there is a lowlatency data transmission during OFDM symbols when a low latency datatransmission is permitted to begin. This implies UE monitors controlinformation at configured locations and the control information, ifreceived and detected by the UE, notifies the UE about an imminent DLdata transmission in a time interval during which a downlinktransmission can start. A low latency UE in the FIG. 7 embodiment, thatis not receiving a low latency data transmission, would need to monitorcontrol information in every one of the first eight downlink OFDMsymbols to determine whether there is a low latency data transmissionscheduled for it.

Note that transmission to different UEs may coexist in an overlappingmanner, in time and/or frequency, and part of the transmission of one UEmay overlap with the control region of another UE's transmission. Forexample, transmission of UE 102 a may potentially overlap with thecontrol region of UE 102 b. The network may configure some controlregions by RRC signaling in one or more symbols (the configured controlregions may or may not have any associated periodicity) and provide theinformation to one or more UEs. When the UEs receive a transmissionoverlapping the control region and if they are aware of the configuredregion, the UEs may not receive data in the overlapping region eventhough the transmission overlaps the region in time (e.g., transmissionof the UE is rate-matched around the critical region, if the region isknown to UE). Alternatively, the UE may receive data in the overlappingregion, and if another later transmission to a different UE is receivedin the overlapping region, transmission of the former UE can bepre-empted by the later transmission in the overlapping region. Asdiscussed below, some control signaling with update of resourceassignment may be signalled to the first UE.

In the embodiments illustrated in FIGS. 6 and 7, any downlinktransmissions to a low latency UE use resources that are also used tosend downlink transmissions to latency tolerant UEs. Therefore, a jointtransmission scheme may be used to try to overcome interference, e.g.using different code resources to transmit the latency tolerant data andthe low latency data. Alternatively, whenever a low latency datatransmission is scheduled during the latency tolerant interval, thelatency tolerant data to be transmitted on the low latency resources maybe punctured or withheld for later downlink transmission. A controlsignal may notify the affected latency tolerant UEs that the latencytolerant data transmission has been punctured or withheld. The controlsignal may be multiplexed in one or more locations during thetransmission of low latency or latency tolerant traffic. The latencytolerant UE may monitor for control signals containing puncturinginformation in one or more locations (configured in time and/orfrequency) after a latency tolerant transmission has been scheduled. Thenumber of monitoring locations may depend on duration of the low latencytransmission, as the latency tolerant transmission duration may spanmultiple configured locations for the presence of control signals.

FIG. 8 illustrates a portion of time/frequency resources 302, accordingto another embodiment. A duration in time equal to one latency tolerantinterval is illustrated. The illustrated time interval is “uplinkdominated” because it includes more uplink OFDM symbols than downlinkOFDM symbols. Also, the illustrated time interval is a self-containedTDD time interval equal to the latency tolerant interval. Even thoughFIG. 8 shows overlap of different low latency slots in an interval wherethere is DL to UL switching, the principle of overlapping transmissionand slot architecture can be applicable to any UL resources, in TDD andFDD systems.

Multiple low latency uplink slots coexist and are labelled in FIG. 8 as“S1” to “S8”. The different low latency slots may be used by differentlow latency UEs, and the start time of each low latency slot can occurat the start of any symbol. For the uplink, the network can configure ULresources to different UEs in an overlapping manner and startingpositions for different transmissions from different UEs can beconfigured with different intervals, i.e., value of x can be differentfor different UEs. Each low latency slot is 7 OFDM symbols in duration,but this is only an example. In general, some low latency slots mayoverlap in time and frequency, e.g. S2 and S3. Also, some low latencyslots may overlap in time, but are mapped to other orthogonal ornon-orthogonal resources. For example, a low latency UE sending a grantfree uplink transmission during slot S5 overlaps in time with anotherlow latency UE sending a grant free uplink transmission during slot S6,but the two grant free uplink transmissions are mapped to orthogonalfrequency resources. Alternatively, some or more UL transmissions can begrant-based. A UE supporting grant-based transmissions can be configuredto monitor control signaling every x symbols in DL resources. If controlsignaling indicating a grant is received (e.g., in the DL symbols at thebeginning of the interval), the UE can start its UL transmissionpotentially at any symbol within the UL symbols of the interval in FIG.8. Similar to DL transmission, the start position of the UL transmissioncan be flexible for both grant-based and grant-free transmissions.Similarly to the DL, a UE can be configured to start its transmission inUL resources every x symbols. In some cases, a UE may not be able tostart its UL transmission in one or more of every x symbols, if thesymbols are no longer available for UL transmissions, e.g., if the slotformat changes.

In the embodiment of FIG. 8, the uplink resources are partitioned intothree frequency regions 304, 306, and 308. A mapping known to the lowlatency UEs and the base station may provide information indicating theregion 304 or 306 or 308 in which the low latency UE is to transmit.This implies semi-statically some resource partitions are indicated tothe UEs. The region 304 or 306 or 308 in which a low latency UE is totransmit may be based on the uplink OFDM symbol at which the low latencyUE begins its uplink data transmission. Also, the embodiment of FIG. 8could be used for acknowledgement/negative acknowledgement (“A/N”)-lessuplink low latency data transmission, in which case all of the symbolscould be uplink symbols. If the uplink low latency data transmission isinstead A/N-based, then the number of uplink OFDM symbols interposedbetween downlink OFDM symbols may be reduced in order to provide morefrequent opportunities for A/N on the downlink.

FIG. 9 illustrates a portion of time/frequency resources 352, accordingto another embodiment. A duration in time equal to one latency tolerantinterval is illustrated. The illustrated time interval is downlinkdominated. Individual OFDM symbols are not illustrated.

Low latency UEs 102 a and 102 b are opportunistically scheduled in thecoexistence region. The slot start time of the low latency datatransmissions may be flexible, e.g. as described above. However, in FIG.9 downlink dominated low latency self-contained intervals are scheduledwithin the DL portion of a latency tolerant interval in the coexistenceregion, as shown at 356 and 358. Therefore, a latency tolerant intervalmust be greater than or equal to a low latency interval in thisembodiment. It is contemplated that the latency tolerant region and thecoexistence region may use different numerologies.

The latency tolerant data to be transmitted on the scheduled downlinklow latency resources 362 and 364 may be jointly transmitted, orpunctured, or withheld for later downlink transmission. A control signalmay notify affected latency tolerant UEs that the latency tolerant datatransmission has been punctured or withheld. During the guard period anduplink portions of the low latency self-contained intervals 356 and 358,there is no downlink transmission, not even in the latency tolerant UEregion, in order to mitigate interference.

The frequency of a control indicator notifying the latency tolerant UEsof the presence of a self-contained low latency interval may beconfigurable. The location of the control indicator may bepre-configured. The interval between pre-configured locations of theindicator may be equal or shorter than a low latency slot duration, sothat low latency transmissions can be initiated more frequently thanonce per slot duration. For example, if the slot duration is threesymbols and a low latency transmission may be initiated at any symbol,then the frequency of the control indicator is every symbol. Thisimplies a scenario where duration of DL symbols within the latencytolerant interval can be long and ACK/NACK (“A/N”) feedback of anyscheduled low latency transmission would have to wait at least until theUL symbols at the end of the latency tolerant interval. To provideopportunities for faster A/N feedback, one or more low latencytransmissions can be scheduled with an associated UL resource that isassigned before the UL symbols in the latency tolerant interval,potentially in the symbols that were previously configured as DLsymbols. A DL control signaling, either UE specific or group-common,notifies the UEs of switching some of the DL symbols to UL symbols,e.g., notifies the latency tolerant UEs of the presence of low latencytransmission and that low latency DL transmission is accompanied by oneor more UL symbols. Latency tolerant UEs do not receive any transmissionduring the guard period and UL symbols. The DL control signalingnotifying the change (i.e., some DL symbols of latency tolerant intervalconverted to GP/Unknown and UL symbols) may be received in the samesymbol where control signaling scheduling the low latency transmissionis received, or at different symbols, either before or after the lowlatency transmission begins. In one example, the control signaling (forthis potential switch of DL→UL or GP/Unknown) may be monitored with aconfigured periodicity within the DL symbols of a TDD system. Forexample, if the configured duration (e.g., a slot) originally contains NDL symbols, then the UE can monitor for the dynamic signaling every Ksymbols where 1<=K<N, which may indicate over-riding of some DL symbolsto GP/Unknown and/or UL symbols. In one example, the DL controlsignaling indicating the switch, may provide location of the GP/Unknownand/or UL symbols to both latency tolerant and low latency UEs. In oneexample, the DL signaling only indicates Unknown symbols to representthe newly converted DL symbols. Latency tolerant UEs will neitherreceive nor transmit in the symbols indicated as Unknown. Low latencyUEs may receive an indication of A/N resources in the DL schedulinggrant in one or more of the Unknown symbols, i.e., UE specific DCI oflow latency UEs over-rides one or more Unknown symbols to UL symbols.This procedure provides DL low latency transmission to have faster A/Nopportunity within a TDD frame structure where originally configured DLdurations may be long and instead of always providing frequent ULtransmission opportunity, UL resources are configured on-demand basis,especially when there is a low latency DL transmission scheduledrequiring faster A/N feedback. DL control signaling indicating theswitch is only transmitted when there is a need to switch. However, theUEs may still need to monitor at the configured locations. The DLcontrol signaling may indicate a set of contiguous symbols within areference interval (such as within a group of OFDM symbols within the DLsymbols of the latency tolerant interval) as Unknown and/or UL. Forexample, with respect to a reference position such as start of DLsymbols or any other location, the signaling may indicate one or both ofa starting position and duration, or one or both of a starting andending position. If duration/length of contiguous symbols ispre-configured, indicating a starting position may be enough. Then,unless overridden by a DCI or PDCCH, UEs assume no action on the symbolsindicated as Unknown. The indicated UL symbols, if any, can be used byeither or both of low latency and latency tolerant UEs. Newly convertedUL symbols can be used for Scheduling Request (SR), or SoundingReference Signal (SRS) transmissions as well as, A/N feedback. In oneexample, latency tolerant UEs may be configured to use the UL symbols totransmit early A/N feedback. In another example, either or both lowlatency and latency tolerant UEs can be configured to transmit A/Nfeedback in the indicated UL symbols.

In some embodiments, the low latency data transmission in low latencyself-contained intervals 356 and 358 may have a different numerologycompared to the latency tolerant data transmissions. For example, thelatency tolerant data transmissions may use a 30 kHz subcarrier spacing,and the low latency data transmissions may use a 60 kHz subcarrierspacing. By using a 60 kHz subcarrier spacing instead of a 30 kHzsubcarrier spacing, the OFDM symbols of the low latency transmissionswould be shorter than the OFDM symbols of the latency toleranttransmissions. This can be achieved by using two different numerologieswith symbol alignment, such that the start and end times of at leastsome of the symbols of one numerology align with start and end times ofsymbols of the other numerology. In this embodiment, a filter or othersuitable means may be used to reduce the interference between thelatency tolerant transmissions and the low latency transmissions ofdifferent numerologies.

FIG. 10 illustrates a portion of downlink time/frequency resources 372,according to another embodiment. Because all of the illustratedresources are downlink resources, the notation “D” has not been added.Also, individual OFDM symbols are not illustrated in FIG. 10.

The resources 372 are partitioned into a latency tolerant UE region 374and a coexistence region 376, which may or may not have the samenumerology. There is dynamic resource sharing between the latencytolerant communications and the low latency communications in thecoexistence region 376. It is contemplated that the latency tolerantregion and the coexistence region may use different numerologies.

Larger latency tolerant data packets are scheduled in the latencytolerant UE region 374, e.g. packets that, when encoded, are theduration of a latency tolerant interval. The scheduling granularity ofthe coexistence region 376 is smaller than the scheduling granularity ofthe latency tolerant region 374. For example, in FIG. 10 there are fourscheduling intervals in the coexistence region 376 for every one latencytolerant interval. Each scheduling interval in the coexistence region376 is equal to a low latency slot duration. Smaller latency tolerantdata packets are scheduled in the coexistence region 376, in particularpackets that, when encoded, correspond to the scheduling interval in thecoexistence region. It is contemplated that low latency traffic in thecoexistence region 376 may have a different scheduling granularity thanlatency tolerant traffic in the coexistence region 376. For example, thescheduling interval of the latency tolerant traffic in the coexistenceregion 376 may be an integer multiple of the scheduling interval of thelow latency traffic in the coexistence region 376.

Latency tolerant data packets may be scheduled in the coexistence regionat every latency tolerant interval, or at shorter intervals. Thescheduling of latency tolerant data packets in each latency tolerantinterval in the coexistence region is performed by bundling the four lowlatency slot durations. For example, latency tolerant data packets 380,381, 382, and 383 are scheduled at the start of the second illustratedlatency tolerant interval. It is contemplated that more or fewer thanfour low latency slots may be bundled. Each of the latency tolerant datapackets 380, 381, 382, 383 is separately encoded to correspond to theduration of the low latency slot. However, low latency data 390 arrivesto be transmitted during the second low latency slot of the secondlatency tolerant interval in the coexistence region. Scheduled latencytolerant packet 382 is therefore withheld from transmission. Note thatin this embodiment, scheduled latency tolerant packet 382 is notpunctured or jointly transmitted, but is instead held back andtransmitted at a later time, e.g. as illustrated at 391. In thisembodiment, the receiver of the data packets 380, 381, 383 is able todecode each of these packets without receiving the data packet 382,because all four data packets 380, 381, 382, 383 are separately encoded.As a result, the transmission of low latency data 390 does not interferewith the reception of the data packets 380, 381, 383, and does notnecessitate retransmission of the data packets 380, 381, 383.

FDM provides the flexibility to schedule eMBB (more generally latencytolerant UEs) and URLLC (more generally low latency UEs) together inshared resources. In FIG. 10, an example is shown where two regions areidentified: eMBB only region and coexistence region. Large packets ofeMBB data can be scheduled in the eMBB only region, whereas some smalleMBB packets may coexist with URLLC traffic in the coexistence region.To lower overhead, eMBB can be scheduled by bundling multiple URLLCslots in the coexistence region. If URLLC packets arrive after eMBB isscheduled, the system postpones transmission of one or more packets ofeMBB and assigns the resources to URLLC traffic. eMBB UEs can benotified of this during the transmission. This does not requirepuncturing, which is otherwise needed for TDM based coexistence wheneMBB has longer interval than URLLC slot.

Low latency packets scheduled in the coexistence region 376 are labelled“LL” in FIG. 10. Although not illustrated, a low latency packet may bescheduled in the first scheduling interval of a latency tolerantinterval. In any case, suitable control information is needed to informthe affected latency tolerant UEs that transmission of a latencytolerant packet in the coexistence region 376 has been postponed. Insome embodiments, the control information notifying a latency tolerantUE that a latency tolerant packet transmission has been postponed may bemultiplexed with the low latency control information at the start of thelow latency slot. The low latency control information would indicate tothe low latency UE that a low latency data transmission has beenscheduled in the slot.

During operation, larger latency tolerant packets are scheduled in thelatency tolerant region 374. The latency tolerant UEs receiving data inregion 374 do not need to monitor control information to see if thetransmission has been interrupted by a low latency transmission becauseregion 374 is dedicated to the transmission of latency tolerant data.Smaller latency tolerant packets are scheduled in the coexistence region376, and the latency tolerant UEs receiving data in coexistence region376 monitor control information to see if the transmission of any oftheir scheduled packets has been interrupted and postponed by a lowlatency transmission. This implies that if the data of latency tolerantUEs overlaps with the configured time-frequency resources 376 where bothtraffic can be scheduled (i.e., region 130 in FIG. 1), then the latencytolerant UEs will have to monitor for an indication that provides anupdate of scheduling assignment or puncturing information. Aconfiguration indication can be provided to the UEs to turn onmonitoring the puncturing indication, which the UE does after its datais scheduled overlapping the configured coexistence region. Thepuncturing indication payload that provides pre-emption or puncturinginformation to one or more UEs can include or be appended with a CyclicRedundancy Check (CRC) to facilitate error correction or detection. TheCRC can be masked or scrambled with an identifier specific to theintended receiver or group of receivers (e.g. a Radio Network TemporaryIdentifier (RNTI) as used in a conventional PDCCH structure tofacilitate blind detection. The indication payload can be encoded withdifferent channel coding techniques such as Polar coding, Low-DensityParity-Check (LDPC) coding, and Turbo coding. and modulated withdifferent modulation schemes such asBinary Phase-Shift Keying (BPSK),Quadrature Phase Shift Keying (QPSK), M-ary Quadrature AmplitudeModulation (M-QAM), where M can be any integer multiple of 2 or can be2^(N), where N is a positive integer. For example, N can be one of {1,2, 3, 4, 5, 6, 7, 8}. A Demodulation Reference Signal (DMRS) density canbe J/K<1, where J and K are positive integers. For example, J can be 1and K can be one of {2, 3, 4, 5, 6, 7, 8}. In another example, J can be2 and K can be one of {3, 5, 7}. A set of DMRS densities may beconfigured at the UE and one can be used (by the UE) for a givennumerology. Interleaving amongst Resource Element Groups (REGs) orbundles of REGs (bundle size can be of size 2, 3, 4, 5 or 6) can also beused to increase robustness. For each carrier, a puncturing indication(PI) can be configured, i.e., if a UE receives a transmission overmultiple carriers, it may need to monitor for a PI in each carrier.Alternatively, a PI can be configured addressing pre-emption overmultiple carriers and the UE monitors for a PI in only one of theaggregated carrier where a PI is configured.

In an example, latency tolerant UEs receive control information at thebeginning of the latency tolerant interval, regardless of whether a lowlatency packet is scheduled in the first slot or later. If low latencytraffic comes in the first slot, the control signals for the latencytolerant and low latency traffic are multiplexed in the first fewsymbols of the first slot. The control information may notify thelatency tolerant UE that the first slot is no longer assigned to thelatency tolerant communication, but the remaining slots or parts of theremaining slots are assigned to the latency tolerant communication. Inaddition, if transmission of one or more bundled eMBB (latency tolerant)slots is postponed, a low overhead indicator can notify the eMBB(latency tolerant) UE of the updated scheduling. The postponed orpunctured transmission can be further scheduled by the base station at alater time.

In an alternative example, the latency tolerant UE has the option toreceive regular control information in any of the slots. For example, ifthe first slot is used for URLLC (a low latency UE), then if the latencytolerant UE did not detect a control signal in the first slot, thelatency tolerant UE will look for regular control information insubsequent slots.

Scheduling can be done bundling 4 slots, 3 slots, 2 slots, orindividually, for latency tolerant data. For example, control forbundling two slots may come in the 3^(rd) slot, when an intervalcontains four slots.

FIGS. 11 and 12 illustrate some specific examples of the embodimentsdescribed above in relation to FIG. 10. In FIGS. 11 and 12, any guardperiod and uplink period are respectively labelled “GP” and “U”. Theremaining portion of the time/frequency resources 372 are for downlinktransmission. Example low latency data opportunistically scheduled isindicated using “LL”. Individual OFDM symbols are not illustrated inFIGS. 11 and 12.

In FIG. 11, the co-existence region 376 has a numerology different fromthe latency tolerant region 374. Specifically, the subcarrier spacing inthe co-existence region is 60 kHz, and the subcarrier spacing in thelatency tolerant region is 30 kHz. Also, there are two downlink lowlatency slots in one 0.25 ms interval.

Therefore, in some embodiments, frequency division multiplexed (FDM)based numerology multiplexing may be used for latency tolerantcommunication and low latency communication coexistence. In someembodiments, the same slot definition, e.g. seven OFDM symbols, can beused for different numerologies, which may simplify implementation. Insome embodiments, orthogonal resource allocation may be used for the lowlatency communications and the latency tolerant communications, forexample by using different time/frequency resources. Alternatively,non-orthogonal resource allocation may be used, such as SCMA.

In FIG. 11, we show an example where we identify an eMBB only region(i.e. a latency tolerant UE region) and a coexistence region. Large eMBBpackets are scheduled over a longer interval (e.g., 0.25 ms or longer)in the eMBB only region. In the coexistence region, URLLC and eMBB canbe jointly scheduled, in particular small eMBB packets can be assignedin that region. Multiple URLLC slots (e.g., each slot can be of 0.125ms) can fit within an eMBB interval. eMBB packets may adopt bundling ofURLLC slots in the coexistence region with common control information atthe beginning of each 0.25 ms interval, which reduces overhead.

In FIG. 12, the numerology is the same in both regions 374 and 376: 60kHz subcarrier spacing. There are two self-contained TDD intervals inthe illustrated 0.25 ms time interval. A possible benefit of FIG. 12compared to FIG. 11 is that uplink acknowledgements and negativeacknowledgements may be sent with lower latency because there is anuplink period every 0.125 ms.

Switching time between downlink and uplink can be set to 0.25 ms or0.125 ms depending on the latency restriction on URLLC, overhead, andother considerations. Note that this approach does not requirepuncturing because if resources of eMBB slots are scheduled to URLLC,the eNodeB will attempt to transmit the eMBB packet from that slot at alater time, thus requiring no changes in hybrid automatic repeat request(HARQ) procedure (e.g., code block level HARQ, outer code to protecteMBB transmission from bursty interference, or weighted HARQ combiningto account for degraded transmissions). If transmission of one or morebundled eMBB slots is postponed or punctured, a low overhead indicatorcan notify the eMBB UE of the updated scheduling. A UE specific orcommon search space in one or more DL symbols can be configured forlatency tolerant UEs to receive puncturing indication and based on thecurrent slot format (i.e., which symbols are DL, UL, Gap/Unknown), theUEs may skip some monitoring occasions of puncturing indication.

As discussed in embodiments above, the start time or location of a timeinterval (e.g. slot) for a downlink transmission to a UE may be moreflexible. For example, and as described earlier in reference to FIG. 3,instead of beginning at predetermined starting points in a frame orsubframe, a downlink transmission time interval may instead possiblybegin every x OFDM symbols. x may be as small as one OFDM symbol. A UEis therefore configured to monitor for control information on a periodicbasis, where the control information indicates a downlink transmissionfor the UE. The UE may be instructed to monitor for the controlinformation once every x OFDM symbols.

FIG. 13 is a method performed by the base station 100 and two UEs,according to one embodiment. The two UEs will be referred to as “UE 1”and “UE 2”. In step 422, the base station 100 sends monitoringconfiguration signaling to UE 1. The monitoring configuration signalingwill be referred to as a “monitoring configuration indication” in FIG.13. The monitoring configuration indication indicates when UE 1 is tomonitor for control information. For example the configurationindication may indicate the specific OFDM symbols where monitoring is tobe done, a periodicity of the monitoring, and/or the start locationswhere a downlink transmission time interval (as indicated by the controlinformation) may begin. In FIG. 13, the configuration indicationindicates a monitoring periodicity of x OFDM symbols for UE 1. Forexample, if assuming the FIG. 5 embodiment, the first downlink OFDMsymbol at which the UE 1 is to monitor for control information is thefirst downlink OFDM symbol illustrated in FIG. 5, and the periodicity isx=1, such that UE 1 is instructed to monitor for the control informationat the start of each OFDM symbol, as shown at 224 in FIG. 5. The controlinformation indicates a downlink transmission for the UE 1. The controlinformation may be a downlink scheduling grant.

In step 423, UE 1 monitors for the control information according to themonitoring configuration indication.

In step 424, the base station 100 also sends monitoring configurationsignaling (referred to as a monitoring configuration indication) to UE2. The monitoring configuration indication indicates, for UE 2 when UE 2is to monitor for control information. As for UE 1, the configurationindication for UE 2 may indicate the specific OFDM symbols wheremonitoring is to be done, a periodicity of the monitoring, and/or thestart locations where a downlink transmission time interval (asindicated by the control information) may begin. In general, the OFDMsymbols at which UE 2 monitors for control information may be differentfrom the OFDM symbols at which UE 1 monitors for control information. Anexample of this can be seen in relation to FIG. 6: if UE 1 is UE 102 ain FIG. 6 and UE 2 is UE 102 b in FIG. 6, then the first OFDM symbolcorresponding to UE 102 a (the second OFDM symbol in the illustratedtime interval) is different from the first OFDM symbol corresponding toUE 102 b (the sixth OFDM symbol in the illustrated time interval).

In general, the monitoring periodicity of UE 1 and UE 2 may bedifferent. In the example in FIG. 13, UE 1 is configured to monitor forthe control information every x OFDM symbols, and UE 2 is configured tomonitor for the control information every z OFDM symbols. However x mayequal z.

In step 426, control information is sent to UE 1 in a downlink OFDMsymbol monitored by UE 1. The control information indicates that thereis a downlink transmission coming from the base station 100 to UE 1 in aparticular time interval. In some embodiments, the control informationmay be a downlink scheduling grant.

In step 428, the downlink transmission is sent from the base station 100to UE 1. The downlink transmission has a duration of k OFDM symbols. Insome embodiments, the downlink transmission for UE 1 can begin any onesymbol within the particular time interval (e.g. m>N/k possible OFDMsymbol locations within the time interval). But other possibilitiesexist for the downlink transmission.

As an example, if UE 1 is UE 102 a in FIG. 6, then the controlinformation in step 426 is sent in the second downlink OFDM symbol inthe illustrated time interval, and the control information and datatransmission have a duration of three OFDM symbols. The second downlinkOFDM symbol in the illustrated time interval may carry only the controlinformation, or it may carry both the control information and some ofthe data transmission.

Returning to FIG. 13, in step 429 UE 2 monitors for its controlinformation according to its monitoring configuration indication, whichwas sent to it in step 424. Step 429 can occur in parallel to theactivities of UE 1, e.g. step 429 may occur in parallel to steps 426 and428.

In step 430, control information is sent to UE 2 in a downlink OFDMsymbol monitored by UE 2. The control information indicates that thereis a downlink transmission coming from the base station 100 to UE 2during a particular time interval. In some embodiments, the controlinformation may be a downlink scheduling grant.

In step 432, the downlink transmission is sent from the base station 100to UE 2. The downlink transmission has a duration of y OFDM symbols. Ingeneral, k≠y, although k may be equal to y. The downlink transmissionfor UE 2 can also begin at any one symbol within the particular timeinterval (e.g. m>N/k possible OFDM symbol locations) but it isunderstood that other possibilities exist for the downlink transmissionsuch as the example shown in FIG. 6.

Optionally, in step 434, at some point in the future the monitoringconfiguration is updated for UE 1. As an example, the monitoringconfiguration may be updated so that UE 1 instead monitors for controlinformation once every n≠x downlink OFDM symbols.

Optionally, in step 436, at some point in the future the monitoringconfiguration is updated for UE 2. As an example, the monitoringconfiguration may be updated so that UE 2 no longer monitors for controlinformation.

Optional steps 434 and 436 are illustrated in FIG. 13.

FIG. 14 is a method performed by a UE, according to one embodiment. Instep 452, the UE receives configuration signaling. The configurationsignaling indicates a plurality of start locations. Each start locationoccurs x OFDM symbols apart from an adjacent start location.

In step 454, for each one of at least some of the plurality of startlocations, the UE monitors for control information at that startlocation. The control information indicates that a downlink datatransmission for the UE has been scheduled during a particular timeinterval that begins at that start location.

In step 456, for one of the at least some of the plurality of startlocations, the UE receives the control information and the downlink datatransmission during the particular time interval.

FIG. 15 is a method performed by a base station, according to anotherembodiment. In step 472, the base station transmits, to a UE,configuration signaling. The configuration signaling indicates aplurality of start locations, each of which the UE is to monitor forcontrol information. Each start location occurs x OFDM symbols apartfrom an adjacent start location.

In step 474, the base station transmits control information at aparticular start location of the plurality of start locations. Thecontrol information indicating that a downlink data transmission for theUE has been scheduled during a time interval that begins at theparticular start location.

In step 476, the base station transmits the downlink data transmissionduring the time interval.

FIG. 16 is a method according to another embodiment. In step 502, dataof a first type (e.g. latency tolerant data) is transmitted during atime interval. The time interval has N OFDM symbols. The time intervalmay be part of or all of a latency tolerant interval. In step 504, dataof a second type (e.g. low latency data) is transmitted within the timeinterval. The data of a second type has a duration of k<N OFDM symbols.The transmission of the data of the second type can begin at one ofm>N/k possible OFDM symbol locations within the time interval. Theflexibility of having the data of the second type beginning at one ofm>N/k possible OFDM symbol locations may allow for reduced latencytransmission.

In some embodiments, the data of the first type is latency tolerantdata, and the data of the second type is low latency data.

In some embodiments, transmitting the data of the second type includestransmitting a first slot of k OFDM symbols, and the method may furtherinclude: transmitting a second slot of k OFDM symbols, the second slotalso beginning at one of m>N/k possible OFDM symbol locations within thetime interval.

In some embodiments, the first slot and the second slot do not useoverlapping time/frequency resources.

In some embodiments, the first slot and the second slot use at leastsome overlapping time/frequency resources.

In some embodiments, m≤N−k+1.

In some embodiments, m=N−k+1, and the transmission of data of the secondtype begins at one of the first N−k+1 OFDM symbol locations within thetime interval.

In some embodiments, the time interval having the N OFDM symbols is thedownlink portion of a TDD self-contained interval, and the data of thefirst type and the data of the second type is downlink data.

In some embodiments, the time interval having the N OFDM symbols is theuplink portion of a TDD self-contained interval, and the data of thefirst type and the data of the second type is uplink data.

In some embodiments, the time interval having the N OFDM symbols is thedownlink portion of a TDD self-contained interval, the data of a secondtype includes downlink OFDM symbols and uplink OFDM symbols, and a guardperiod is interposed between the downlink OFDM symbols and the uplinkOFDM symbols.

In some embodiments, the transmission of the data of the second typeoccurs using time/frequency resources that are scheduled for use intransmitting particular data of the first type, and the method furtherincludes delaying transmission of the particular data of the first type.

FIG. 17 is a method performed by a base station, according to anotherembodiment. In step 522, a plurality of data packets to be transmittedto a first UE is scheduled on first resources. The first UE may be alatency tolerant UE, and the data packets may carry latency tolerantdata. In step 524, instead of transmitting one of the data packets on aportion of the first resources, other data is transmitted on the portionof the first resources. The other data may be low latency data for a lowlatency UE. In step 526, the base station signals to the first UE thatone of the data packets was not transmitted on the portion of the firstresources.

In some embodiments, data in the plurality of data packets is latencytolerant data, and the other data is low latency data.

In some embodiments, the method further includes scheduling data packetslarger than each of the plurality of data packets on second resources.

In some embodiments, the subcarrier spacing of the second resources isdifferent from the subcarrier spacing of the first resources.

In some embodiments, a base station is configured to perform any one ofthe method embodiments described herein.

In some embodiment, a system is configured to perform any one of themethod embodiments described herein. The system may include a pluralityof UEs.

Other Example Operating Environments

FIG. 18 illustrates an example communication system 1100 in whichembodiments of the present disclosure could be implemented. In general,the system 1100 enables multiple wireless or wired elements tocommunicate data and other content. The purpose of the system 1100 maybe to provide content (voice, data, video, text) via broadcast,narrowcast, user device to user device, etc. The system 1100 may operateefficiently by sharing resources such as bandwidth.

In this example, the communication system 1100 includes electronicdevices (ED) 1110 a-1110 c, radio access networks (RANs) 1120 a-1120 b,a core network 1130, a public switched telephone network (PSTN) 1140,the Internet 1150, and other networks 1160. While certain numbers ofthese components or elements are shown in FIG. 18, any reasonable numberof these components or elements may be included in the system 1100.

The EDs 1110 a-1110 c are configured to operate, communicate, or both,in the system 1100. For example, the EDs 1110 a-1110 c are configured totransmit, receive, or both via wireless communication channels. Each ED1110 a-1110 c represents any suitable end user device for wirelessoperation and may include such devices (or may be referred to) as a userequipment/device (UE), wireless transmit/receive unit (WTRU), mobilestation, mobile subscriber unit, cellular telephone, station (STA),machine type communication device (MTC), personal digital assistant(PDA), smartphone, laptop, computer, touchpad, wireless sensor, orconsumer electronics device. The UEs described earlier and introduced inFIGS. 1 and 2 are examples of EDs. More generally, the UEs describedearlier and introduced in FIGS. 1 and 2 may be replaced with EDs.

In FIG. 18, the RANs 1120 a-1120 b include base stations 1170 a-1170 b,respectively. Each base station 1170 a-1170 b is configured towirelessly interface with one or more of the EDs 1110 a-1110 c to enableaccess to any other base station 1170 a-1170 b, the core network 1130,the PSTN 1140, the Internet 1150, and/or the other networks 1160. Forexample, the base stations 1170 a-1170 b may include (or be) one or moreof several well-known devices, such as a base transceiver station (BTS),a Node-B (NodeB), an evolved NodeB (eNodeB), a Home eNodeB, a gNodeB(sometimes called a “gigabit” NodeB), a transmission point (TP), atransmit/receive point (TRP), a site controller, an access point (AP),or a wireless router. The base station 100 introduced earlier is anexample of one of base stations 1170 a-1170 b.

Any ED 1110 a-1110 c may be alternatively or jointly configured tointerface, access, or communicate with any other base station 1170a-1170 b, the internet 1150, the core network 1130, the PSTN 1140, theother networks 1160, or any combination of the preceding. Optionally,the system may include RANs, such as RAN 1120 b, wherein thecorresponding base station 1170 b accesses the core network 1130 via theinternet 1150, as shown.

The EDs 1110 a-1110 c and base stations 1170 a-1170 b are examples ofcommunication equipment that can be configured to implement some or allof the functionality and/or embodiments described herein. In theembodiment shown in FIG. 18, the base station 1170 a forms part of theRAN 1120 a, which may include other base stations, base stationcontroller(s) (BSC), radio network controller(s) (RNC), relay nodes,elements, and/or devices. Any base station 1170 a, 1170 b may be asingle element, as shown, or multiple elements, distributed in thecorresponding RAN, or otherwise. Also, the base station 1170 b formspart of the RAN 1120 b, which may include other base stations, elements,and/or devices. Each base station 1170 a-1170 b may be configured tooperate to transmit and/or receive wireless signals within a particulargeographic region or area, sometimes referred to as a coverage area. Acell may be further divided into cell sectors, and a base station 1170a-1170 b may, for example, employ multiple transceivers to provideservice to multiple sectors. In some embodiments a base station 1170a-1170 b may be implemented as pico or femto nodes where the radioaccess technology supports such. In some embodiments, multiple-inputmultiple-output (MIMO) technology may be employed having multipletransceivers for each coverage area. The number of RAN 1120 a-1120 bshown is exemplary only. Any number of RAN may be contemplated whendevising the system 1100.

The base stations 1170 a-1170 b communicate with one or more of the EDs1110 a-1110 c over one or more air interfaces 1190 using wirelesscommunication links e.g. RF, μWave, IR, etc. The air interfaces 1190 mayutilize any suitable radio access technology. For example, the system1100 may implement one or more channel access methods, such as codedivision multiple access (CDMA), time division multiple access (TDMA),frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), orsingle-carrier FDMA (SC-FDMA) in the air interfaces 1190.

A base station 1170 a-1170 b may implement Universal MobileTelecommunication System (UMTS) Terrestrial Radio Access (UTRA) toestablish an air interface 1190 using wideband CDMA (WCDMA). In doingso, the base station 1170 a-1170 b may implement protocols such as HSPA,HSPA+ optionally including HSDPA, HSUPA or both. Alternatively, a basestation 1170 a-1170 b may establish an air interface 1190 with EvolvedUTMS Terrestrial Radio Access (E-UTRA) using LTE, LTE-A, and/or LTE-B.It is contemplated that the system 1100 may use multiple channel accessfunctionality, including such schemes as described above. Other radiotechnologies for implementing air interfaces include IEEE 802.11,802.15, 802.16, CDMA2000, CDMA2000 1×, CDMA2000 EV-DO, IS-2000, IS-95,IS-856, GSM, EDGE, and GERAN. Of course, other multiple access schemesand wireless protocols may be utilized.

The RANs 1120 a-1120 b are in communication with the core network 1130to provide the EDs 1110 a-1110 c with various services such as voice,data, and other services. Understandably, the RANs 1120 a-1120 b and/orthe core network 1130 may be in direct or indirect communication withone or more other RANs (not shown), which may or may not be directlyserved by core network 1130, and may or may not employ the same radioaccess technology as RAN 120 a, RAN 120 b or both. The core network 1130may also serve as a gateway access between (i) the RANs 1120 a-1120 b orEDs 1110 a-1110 c or both, and (ii) other networks (such as the PSTN1140, the Internet 1150, and the other networks 1160). In addition, someor all of the EDs 1110 a-1110 c may include functionality forcommunicating with different wireless networks over different wirelesslinks using different wireless technologies and/or protocols. PSTN 1140may include circuit switched telephone networks for providing plain oldtelephone service (POTS). Internet 1150 may include a network ofcomputers and subnets (intranets) or both, and incorporate protocols,such as IP, TCP, UDP. EDs 1110 a-1110 c may be multimode devices capableof operation according to multiple radio access technologies, andincorporate multiple transceivers necessary to support such.

It is contemplated that the communication system 1100 as illustrated inFIG. 18 may support a New Radio (NR) cell, which also may be referred toas hyper cell. Each NR cell includes one or more TRPs using the same NRcell ID. The NR cell ID is a logical assignment to all physical TRPs ofthe NR cell and may be carried in a broadcast synchronization signal.The NR cell may be dynamically configured. The boundary of the NR cellmay be flexible and the system dynamically adds or removes TRPs to fromthe NR cell.

In one embodiment, a NR cell may have one or more TRPs within the NRcell transmitting a UE-specific data channel, which serves a UE. The oneor more TRPs associated with the UE specific data channel are also UEspecific and are transparent to the UE. Multiple parallel data channelswithin a single NR cell may be supported, each data channel serving adifferent UE.

In another embodiment, a broadcast common control channel and adedicated control channel may be supported. The broadcast common controlchannel may carry common system configuration information transmitted byall or partial TRPs sharing the same NR cell ID. Each UE can decodeinformation from the broadcast common control channel in accordance withinformation tied to the NR cell ID. One or more TRPs within a NR cellmay transmit a UE specific dedicated control channel, which serves a UEand carries UE-specific control information associated with the UE.Multiple parallel dedicated control channels within a single NR cell maybe supported, each dedicated control channel serving a different UE. Thedemodulation of each dedicated control channel may be performed inaccordance with a UE-specific reference signal (RS), the sequence and/orlocation of which are linked to the UE ID or other UE specificparameters.

In some embodiments, one or more of these channels, including thededicated control channels and the data channels, may be generated inaccordance with a UE specific parameter, such as a UE ID, and/or an NRcell ID. Further, the UE specific parameter and/or the NR cell ID can beused to differentiate transmissions of the data channels and controlchannels from different NR cells.

An ED, such as a UE, may access the communication system 1100 through atleast one of the TRP within a NR cell using a UE dedicated connectionID, which allows one or more physical TRPs associated with the NR cellto be transparent to the UE. The UE dedicated connection ID is anidentifier that uniquely identifies the UE in the NR cell. For example,the UE dedicated connection ID may be identified by a sequence. In someimplementations, the UE dedicated connection ID is assigned to the UEafter an initial access. The UE dedicated connection ID, for example,may be linked to other sequences and randomizers which are used for PHYchannel generation.

In some embodiments, the UE dedicated connection ID remains the same aslong as the UE is communicating with a TRP within the NR cell. In someembodiments, the UE can keep original UE dedicated connection ID whencrossing NR cell boundary. For example, the UE can only change its UEdedicated connection ID after receiving signaling from the network.

In some embodiments, any number of NR cells may be implemented in thecommunication system 1100. For example, FIG. 19 illustrates twoneighboring NR cells in an example communication system, in accordancewith an embodiment of the present disclosure.

As illustrated in FIG. 19, NR cells 1282, 1284 each includes multipleTRPs that are assigned the same NR cell ID. For example, NR cell 1282includes TRPs 1286, 1287, 1288, 1289, 1290, and 1292, where TRPs 1290,1292 communicates with an ED, such as UE 1294. It is obviouslyunderstood that other TRPs in NR cell 1282 may communicate with UE 1294.NR cell 1284 includes TRPs 1270, 1272, 1274, 1276, 1278, and 1280. TRP1296 is assigned to NR cells 1282, 1284 at different times, frequenciesor spatial directions and the system may switch the NR cell ID fortransmit point 1296 between the two NR cells 1282 and 1284. It iscontemplated that any number (including zero) of shared TRPs between NRcells may be implemented in the system.

In one embodiment, the system dynamically updates the NR cell topologyto adapt to changes in network topology, load distribution, and/or UEdistribution. In some implementations, if the concentration of UEsincreases in one region, the system may dynamically expand the NR cellto include TRPs near the higher concentration of UEs. For example, thesystem may expand NR cell to include other TRPs if the concentration ofUEs located at the edge of the NR cell increases above a certainthreshold. As another example, the system may expand NR cell to includea greater concentration of UEs located between two hyper cells. In someimplementations, if the traffic load increases significantly at oneregion, the system may also expand the NR cell associated with theregion to include TRPs for the increased traffic load. For example, ifthe traffic load of a portion of the network exceeds a predeterminedthreshold, the system may change the NR cell ID of one or more TRPs thatare transmitting to the impacted portion of the network.

In another embodiment, the system may change the NR cell ID associatedwith TRP 1296 from the NR cell ID of NR cell 1282 to the NR cell ID ofNR cell 1284. In one implementation, the system can change theassociation of a TRP with different NR cells periodically, such as every1 millisecond. With such a flexible NR cell formation mechanism, all UEscan be served by the best TRPs so that virtually there are no cell edgeUEs.

In yet another embodiment, the shared TRP 1296 can reduce interferencefor UEs located at the boundary between the two NR cells 1282, 1284. UEsthat are located near the boundaries of two NR cells 1282, 1284experience fewer handovers because the shared TRP is associated witheither NR cell at different times, frequencies or spatial directions.Further, as a UE moves between the NR cells 1282, 1284, the transitionis a smoother experience for the user. In one embodiment, the networkchanges the NR cell ID of the TRP 1296 to transition a UE moving betweenNR cells 1282, 1284.

FIGS. 20 and 21 illustrate other example devices that may implement themethods and teachings according to this disclosure. In particular, FIG.20 illustrates an example ED 1110 (e.g one of the UEs in FIG. 1), andFIG. 21 illustrates an example base station 1170 (e.g. base station 100in FIG. 1.). These components could be used in the system 1100 or in anyother suitable system.

As shown in FIG. 20, the ED 1110 includes at least one processing unit1200. The processing unit 1200 implements various processing operationsof the ED 1110. For example, the processing unit 1200 could performsignal coding, data processing, power control, input/output processing,or any other functionality enabling the ED 1110 to operate in the system1100. The processing unit 1200 may also be configured to implement someor all of the functionality and/or embodiments described in more detailabove. Each processing unit 1200 includes any suitable processing orcomputing device configured to perform one or more operations. Eachprocessing unit 1200 could, for example, include a microprocessor,microcontroller, digital signal processor, field programmable gatearray, or application specific integrated circuit.

The ED 1110 also includes at least one transceiver 1202. The transceiver1202 is configured to modulate data or other content for transmission byat least one antenna or NIC (Network Interface Controller) 1204. Thetransceiver 1202 is also configured to demodulate data or other contentreceived by the at least one antenna 1204. Each transceiver 1202includes any suitable structure for generating signals for wirelesstransmission and/or processing signals received wirelessly or by wire.Each antenna 1204 includes any suitable structure for transmittingand/or receiving wireless signals. One or multiple transceivers 1202could be used in the ED 1110, and one or multiple antennas 1204 could beused in the ED 1110. Although shown as a single functional unit, atransceiver 1202 could also be implemented using at least onetransmitter and at least one separate receiver.

The ED 1110 further includes one or more input/output devices 1206 orinterfaces. The input/output devices 1206 facilitate interaction with auser or other devices (network communications) in the network. Eachinput/output device 1206 includes any suitable structure for providinginformation to or receiving/providing information from a user, such as aspeaker, microphone, keypad, keyboard, display, or touch screen,including network interface communications.

In addition, the ED 1110 includes at least one memory 1208. The memory1208 stores instructions and data used, generated, or collected by theED 1110. For example, the memory 1208 could store software instructionsor modules configured to implement some or all of the functionalityand/or embodiments described above and that are executed by theprocessing unit(s) 1200. Each memory 1208 includes any suitable volatileand/or non-volatile storage and retrieval device(s). Any suitable typeof memory may be used, such as random access memory (RAM), read onlymemory (ROM), hard disk, optical disc, subscriber identity module (SIM)card, memory stick, secure digital (SD) memory card, and the like.

As shown in FIG. 21, the base station 1170 includes at least oneprocessing unit 1250, at least one transmitter 1252, at least onereceiver 1254, one or more antennas 1256, at least one memory 1258, andone or more input/output devices or interfaces 1266. A transceiver, notshown, may be used instead of the transmitter 1252 and receiver 1254. Ascheduler 1253 may be coupled to the processing unit 1250. The scheduler1253 may be included within or operated separately from the base station1170. The processing unit 1250 implements various processing operationsof the base station 1170, such as signal coding, data processing, powercontrol, input/output processing, or any other functionality. Theprocessing unit 1250 can also be configured to implement some or all ofthe functionality and/or embodiments described in more detail above.Each processing unit 1250 includes any suitable processing or computingdevice configured to perform one or more operations. Each processingunit 1250 could, for example, include a microprocessor, microcontroller,digital signal processor, field programmable gate array, or applicationspecific integrated circuit.

Each transmitter 1252 includes any suitable structure for generatingsignals for wireless transmission to one or more EDs or other devices.Each receiver 1254 includes any suitable structure for processingsignals received wirelessly or by wire from one or more EDs or otherdevices. Although shown as separate components, at least one transmitter1252 and at least one receiver 1254 could be combined into atransceiver. Each antenna 1256 includes any suitable structure fortransmitting and/or receiving wireless signals. While a common antenna1256 is shown here as being coupled to both the transmitter 1252 and thereceiver 1254, one or more antennas 1256 could be coupled to thetransmitter(s) 1252, and one or more separate antennas 1256 could becoupled to the receiver(s) 1254. Each memory 1258 includes any suitablevolatile and/or non-volatile storage and retrieval device(s) such asthose described above in connection to the ED 1110. The memory 1258stores instructions and data used, generated, or collected by the basestation 1170. For example, the memory 1258 could store softwareinstructions or modules configured to implement some or all of thefunctionality and/or embodiments described above and that are executedby the processing unit(s) 1250.

Each input/output device 1266 facilitates interaction with a user orother devices (network communications) in the network. Each input/outputdevice 1266 includes any suitable structure for providing information toor receiving/providing information from a user, including networkinterface communications.

It should be appreciated that one or more steps of the embodimentmethods provided herein may be performed by corresponding units ormodules, e.g. the units or modules shown in FIGS. 2, 20, and/or 21. Forexample, a signal may be transmitted by a transmitting unit or atransmitting module. A signal may be received by a receiving unit or areceiving module. A signal may be processed by a processing unit or aprocessing module. Other steps may be performed by the transmitter 174,receiver 176, message processor 178, control information processor 179,transmitter 164, receiver 166, resource allocator 168, message processor170, control information generator 169, transceiver 1202, processingunit 1200, transmitter 1252, receiver 1254, scheduler 1253, and/orprocessing unit 1250 described herein. The respective units/modules maybe hardware, software, or a combination thereof. For instance, one ormore of the units/modules may be an integrated circuit, such as FPGAs orASICs. It will be appreciated that where the modules are software, theymay be retrieved by a processor, in whole or part as needed,individually or together for processing, in single or multiple instancesas required, and that the modules themselves may include instructionsfor further deployment and instantiation.

FURTHER EXAMPLES

In view of, and in addition to the above, the following examples aredisclosed.

Example 1

A method comprising: transmitting data of a first type during a timeinterval, the time interval having N OFDM symbols; transmitting data ofa second type within the time interval, the data of the second typehaving a duration comprising k<N OFDM symbols, and the transmissionbeginning at one of m>N/k possible OFDM symbol locations within the timeinterval.

Example 2

The method of example 1, wherein the data of the first type is latencytolerant data, and the data of the second type is low latency data.

Example 3

The method of example 1, wherein transmitting the data of the secondtype comprises transmitting a first slot of k OFDM symbols, and whereinthe method further comprises transmitting a second slot of k OFDMsymbols, the second slot also beginning at one of m>N/k possible OFDMsymbol locations within the time interval.

Example 4

The method of example 3, wherein the first slot and the second slot donot use overlapping time/frequency resources.

Example 5

The method of example 3, wherein the first slot and the second slot useat least some overlapping time/frequency resources.

Example 6

The method of example 1, wherein m≤N−k+1.

Example 7

The method of example 6, wherein m=N−k+1 and the transmission of data ofthe second type begins at one of the first N−k+1 OFDM symbol locationswithin the time interval.

Example 8

The method of example 1, wherein the time interval having the N OFDMsymbols is the downlink portion of a TDD self-contained interval, andwherein the data of the first type and the data of the second type isdownlink data.

Example 9

The method of example 1, wherein the time interval having the N OFDMsymbols is the uplink portion of a TDD self-contained interval, andwherein the data of the first type and the data of the second type isuplink data.

Example 10

The method of example 1, wherein the time interval having the N OFDMsymbols is the downlink portion of a TDD self-contained interval,wherein the data of a second type comprises downlink OFDM symbols anduplink OFDM symbols, and a guard period is interposed between thedownlink OFDM symbols and the uplink OFDM symbols.

Example 11

The method of example 1, wherein the transmission of the data of thesecond type occurs using time/frequency resources that are scheduled foruse in transmitting particular data of the first type, and wherein themethod further comprises delaying transmission of the particular data ofthe first type.

Example 12

A base station configured to perform the method of any one of examples 1to 11.

Example 13

A system configured to perform the method of any one of examples 1 to11.

Example 14

The system of example 13, wherein the system comprises a plurality ofUEs.

Example 15

A method performed by a base station, the method comprising: schedulinga plurality of data packets to be transmitted to a first UE on firstresources; instead of transmitting one of the data packets on a portionof the first resources, transmitting other data on the portion of thefirst resources; signaling to the first UE that the one of the datapackets was not transmitted on the portion of the first resources.

Example 16

The method of example 15, wherein data in the plurality of data packetsis latency tolerant data, and wherein the other data is low latencydata.

Example 17

The method of example 15, further comprising scheduling data packetslarger than each of the plurality of data packets on second resources.

Example 18

The method of example 17, wherein the subcarrier spacing of the secondresources is different from the subcarrier spacing of the firstresources.

Example 19

A base station configured to perform the method of any one of examples15 to 18.

Example 20

A method performed by a UE, the method comprising: receivingconfiguration signaling indicating a plurality of start locations,wherein each start location occurs x OFDM symbols apart from an adjacentstart location; for each one of at least some of the plurality of startlocations, monitoring for control information at that start location,wherein the control information indicates that a downlink datatransmission for the UE has been scheduled during a particular timeinterval that begins at that start location; for one of the at leastsome of the plurality of start locations, receiving the controlinformation and the downlink data transmission during the particulartime interval.

Example 21

The method of example 20, wherein each start location is at a respectiveOFDM symbol.

Example 22

The method of example 20 or 21, wherein x=1.

Example 23

The method of any one of examples 20 to 22, wherein the particular timeinterval comprises one or more OFDM symbols, and wherein the controlinformation is in a first OFDM symbol of the one or more OFDM symbols.

Example 24

The method of any one of examples 20 to 23, comprising monitoring forthe control information only during OFDM symbols when the downlink datatransmission is permitted to begin.

Example 25

The method of any one of examples 20 to 24, wherein the time intervalthat begins at each start location has a same time duration of k OFDMsymbols.

Example 26

The method of example 25, further comprising receiving an indication ofthe time duration.

Example 27

The method of example 25 or 26, wherein the UE does not monitor for thecontrol information at any OFDM symbol that is fewer than k OFDM symbolsahead of a guard period.

Example 28

The method of any one of examples 20 to 27, wherein the plurality ofstart locations are each different from a start location of another timeinterval at which another UE is to monitor for control information meantfor that other UE.

Example 29

The method of any one of examples 20 to 28, wherein the downlink datatransmission is a low latency data transmission.

Example 30

The method of example 23, wherein the first OFDM symbol includes boththe control information and some of the downlink data transmission.

Example 31

The method of any one of examples 20 to 30, wherein the controlinformation indicates that a downlink data transmission for the UE hasbeen scheduled to begin at that start location.

Example 32

The method of example 23, wherein the first OFDM symbol includes thecontrol information and none of the downlink data transmission.

Example 33

The method of any one of examples 20 to 32, wherein the particular timeinterval has a time duration that is different from a corresponding timeduration of another time interval during which another UE may receive adownlink transmission meant for that other UE.

Example 34

The method of any one of examples 20 to 33, wherein the plurality ofstart locations are a first plurality of start locations, and whereinthe method further comprises receiving updated configuration signaling,the updated configuration signaling indicating a second plurality ofstart locations, wherein each start location of the second plurality ofstart locations occurs n OFDM symbols apart from an adjacent startlocation of the second plurality of start locations, and wherein n isdifferent than x.

Example 35

A UE comprising: a receiver to receive configuration signalingindicating a plurality of start locations, wherein each start locationoccurs x OFDM symbols apart from an adjacent start location; a controlinformation processor to, for each one of at least some of the pluralityof start locations, monitor for control information at that startlocation, wherein the control information indicates that a downlink datatransmission for the UE has been scheduled during a particular timeinterval that begins at that start location; the receiver to, for one ofthe at least some of the plurality of start locations, receive thecontrol information and the downlink data transmission during theparticular time interval.

Example 36

The UE of example 35, wherein each start location is at a respectiveOFDM symbol.

Example 37

The UE of example 35 or 36, wherein x=1.

Example 38

The UE of any one of examples 35 to 37, wherein the particular timeinterval comprises one or more OFDM symbols, and wherein the controlinformation is in a first OFDM symbol of the one or more OFDM symbols.

Example 39

The UE of any one of examples 35 to 38, wherein the control informationprocessor is to monitor for the control information only during OFDMsymbols when the downlink data transmission is permitted to begin.

Example 40

The UE of any one of examples 35 to 39, wherein the time interval thatbegins at each start location has a same time duration of k OFDMsymbols.

Example 41

The UE of example 40, wherein the receiver is further to receive anindication of the time duration.

Example 42

The UE of example 40 or 41, wherein the control information processor isto not monitor for the control information at any OFDM symbol that isfewer than k OFDM symbols ahead of a guard period.

Example 43

The UE of any one of examples 35 to 42, wherein the plurality of startlocations are each different from a start location of another timeinterval at which another UE is to monitor for control information meantfor that other UE.

Example 44

The UE of any one of examples 35 to 43, wherein the downlink datatransmission is a low latency data transmission.

Example 45

The UE of example 38, wherein the first OFDM symbol includes both thecontrol information and some of the downlink data transmission.

Example 46

The UE of any one of examples 35 to 45, wherein the control informationindicates that a downlink data transmission for the UE has beenscheduled to begin at that start location.

Example 47

The UE of example 38, wherein the first OFDM symbol includes the controlinformation and none of the downlink data transmission.

Example 48

The UE of any one of examples 35 to 47, wherein the particular timeinterval has a time duration that is different from a corresponding timeduration of another time interval during which another UE is to receivea downlink transmission meant for that other UE.

Example 49

The UE of any one of examples 35 to 48, wherein the plurality of startlocations are a first plurality of start locations, and wherein thereceiver is to: receive updated configuration signaling, the updatedconfiguration signaling indicating a second plurality of startlocations, wherein each start location of the second plurality of startlocations occurs n OFDM symbols apart from an adjacent start location ofthe second plurality of start locations, and wherein n is different thanx.

Example 50

A method performed by a base station, the method comprising:transmitting, to a UE, configuration signaling that indicates aplurality of start locations, each of which the UE is to monitor forcontrol information, wherein each start location occurs x OFDM symbolsapart from an adjacent start location; transmitting control informationat a particular start location of the plurality of start locations, thecontrol information indicating that a downlink data transmission for theUE has been scheduled during a time interval that begins at theparticular start location; transmitting the downlink data transmissionduring the time interval.

Example 51

The method of example 50, wherein each start location is at a respectiveOFDM symbol.

Example 52

The method of example 50 or 51, wherein x=1.

Example 53

The method of any one of examples 50 to 52, wherein the time intervalcomprises a plurality of adjacent OFDM symbols.

Example 54

The method of any one of examples 50 to 52, wherein the time intervalcomprises one or more OFDM symbols, and wherein the particular startlocation is at a first OFDM symbol of the one or more OFDM symbols.

Example 55

The method of example 54, wherein the control information is in thefirst OFDM symbol.

Example 56

The method of any one of examples 50 to 55, wherein the time intervalhas a time duration of k OFDM symbols.

Example 57

The method of any one of examples 50 to 56, wherein the downlink datatransmission is a low latency data transmission.

Example 58

The method of any one of examples 50 to 57, wherein the UE is a firstUE, wherein the configuration signaling is first configurationsignaling, wherein the plurality of start locations is a first pluralityof start locations, and wherein the method further comprises:transmitting, to a second UE, second configuration signaling thatindicates a second plurality of start locations, each of which thesecond UE is to monitor for control information, wherein each startlocation of the second plurality of start locations occurs z OFDMsymbols apart from an adjacent start location of the second plurality ofstart locations.

Example 59

The method of example 58, wherein x=z.

Example 60

The method of example 55, wherein the first OFDM symbol includes boththe control information and some of the downlink data transmission.

Example 61

The method of example 55, wherein the first OFDM symbol includes thecontrol information and none of the downlink data transmission.

Example 62

The method of any one of examples 50 to 61, wherein the time intervalhas a time duration that is different from a time duration of anothertime interval during which another downlink transmission is sent toanother UE.

Example 63

The method of any one of examples 50 to 62, wherein the plurality ofstart locations are a first plurality of start locations, and whereinthe method further comprises transmitting updated configurationsignaling, the updated configuration signaling indicating a secondplurality of start locations, wherein each start location of the secondplurality of start locations occurs n OFDM symbols apart from anadjacent start location of the second plurality of start locations, andwherein n is different from x.

Example 64

The method of any one of examples 50 to 63, further comprisingtransmitting, to the UE, an instruction to stop monitoring for thecontrol information.

Example 65

A base station comprising: a control information generator to generateconfiguration signaling that indicates a plurality of start locations,each of which the UE is to monitor for control information, wherein eachstart location occurs x OFDM symbols apart from an adjacent startlocation; a transmitter to transmit to the UE: the configurationsignaling; the control information at a particular start location of theplurality of start locations, the control information indicating that adownlink data transmission for the UE has been scheduled during a timeinterval that begins at the particular start location; the downlink datatransmission during the time interval.

Example 66

The base station of example 65, wherein each start location is at arespective OFDM symbol.

Example 67

The base station of example 65 or 66, wherein x=1.

Example 68

The base station of any one of examples 65 to 67, wherein the timeinterval comprises a plurality of adjacent OFDM symbols.

Example 69

The base station of any one of examples 65 to 68, wherein the timeinterval comprises one or more OFDM symbols, and wherein the particularstart location is at a first OFDM symbol of the one or more OFDMsymbols.

Example 70

The base station of example 69, wherein the control information is inthe first OFDM symbol.

Example 71

The base station of any one of examples 65 to 70, wherein the timeinterval has a time duration of k OFDM symbols.

Example 72

The base station of any one of examples 65 to 71, wherein the downlinkdata transmission is a low latency data transmission.

Example 73

The base station of any one of examples 65 to 72, wherein the UE is afirst UE, wherein the configuration signaling is a first configurationsignaling, wherein the plurality of start locations is a first pluralityof start locations, and wherein the transmitter is further to: transmit,to a second UE, second configuration signaling that indicates a secondplurality of start locations, each of which the second UE is to monitorfor control information, wherein each start location of the secondplurality of start locations occurs z OFDM symbols apart from anadjacent start location of the second plurality of start locations.

Example 74

The base station of example 73, wherein x=z.

Example 75

The base station of example 70, wherein the first OFDM symbol includesboth the control information and some of the downlink data transmission.

Example 76

The base station of example 70 wherein the first OFDM symbol includesthe control information and none of the downlink data transmission.

Example 77

The base station of any one of examples 65 to 76, wherein the timeinterval has a time duration that is different from a time duration ofanother time interval during which another downlink transmission is tobe sent to another UE.

Example 78

The base station of any one of examples 65 to 77, wherein the pluralityof start locations are a first plurality of start locations, and whereinthe transmitter is further to: transmit updated configuration signaling,the updated configuration signaling indicating a second plurality ofstart locations, wherein each start location of the second plurality ofstart locations occurs n OFDM symbols apart from an adjacent startlocation of the second plurality of start locations, and wherein n isdifferent from x.

Example 79

The base station of any one of examples 65 to 78, wherein thetransmitter is further to: transmit, to the UE, an instruction to stopmonitoring for the control information.

Example 80

A base station comprising a memory and at least one processor, whereininstructions are stored in the memory that, when executed by the atleast one processor, cause the base station to perform any one of thebase station method examples outlined above.

Example 81

A UE comprising a memory and at least one processor, whereininstructions are stored in the memory that, when executed by the atleast one processor, cause the UE to perform any one of the UE methodexamples outlined above.

CONCLUSION

Although the present invention has been described with reference tospecific features and embodiments thereof, various modifications andcombinations can be made thereto without departing from the invention.The description and drawings are, accordingly, to be regarded simply asan illustration of some embodiments of the invention as defined by theappended claims, and are contemplated to cover any and allmodifications, variations, combinations or equivalents that fall withinthe scope of the present invention. Therefore, although the presentinvention and its advantages have been described in detail, variouschanges, substitutions and alterations can be made herein withoutdeparting from the invention as defined by the appended claims.Moreover, the scope of the present application is not intended to belimited to the particular embodiments of the process, machine,manufacture, composition of matter, means, methods and steps describedin the specification. As one of ordinary skill in the art will readilyappreciate from the disclosure of the present invention, processes,machines, manufacture, compositions of matter, means, methods, or steps,presently existing or later to be developed, that perform substantiallythe same function or achieve substantially the same result as thecorresponding embodiments described herein may be utilized according tothe present invention. Accordingly, the appended claims are intended toinclude within their scope such processes, machines, manufacture,compositions of matter, means, methods, or steps.

Moreover, any module, component, or device exemplified herein thatexecutes instructions may include or otherwise have access to anon-transitory computer/processor readable storage medium or media forstorage of information, such as computer/processor readableinstructions, data structures, program modules, and/or other data. Anon-exhaustive list of examples of non-transitory computer/processorreadable storage media includes magnetic cassettes, magnetic tape,magnetic disk storage or other magnetic storage devices, optical diskssuch as compact disc read-only memory (CD-ROM), digital video discs ordigital versatile disc (DVDs), Blu-ray Disc™, or other optical storage,volatile and non-volatile, removable and non-removable media implementedin any method or technology, random-access memory (RAM), read-onlymemory (ROM), electrically erasable programmable read-only memory(EEPROM), flash memory or other memory technology. Any suchnon-transitory computer/processor storage media may be part of a deviceor accessible or connectable thereto. Any application or module hereindescribed may be implemented using computer/processorreadable/executable instructions that may be stored or otherwise held bysuch non-transitory computer/processor readable storage media.

1. A method performed by a user equipment (UE), the method comprising:receiving configuration signaling indicating first and second startlocations, wherein the second start location occurs x OFDM symbols apartfrom the first start location; for each one of the start locations,monitoring for control information at that start location, wherein thecontrol information indicates whether a downlink data transmission forthe UE has been scheduled during a particular time interval; for one ofthe start locations, receiving the downlink data transmission during theparticular time interval.
 2. The method of claim 1, wherein each startlocation is at a respective OFDM symbol.
 3. The method of claim 1,wherein x=1.
 4. The method of claim 1, wherein the particular timeinterval comprises one or more OFDM symbols, and wherein the controlinformation is in a first OFDM symbol of the one or more OFDM symbols.5. The method of claim 1, comprising monitoring for the controlinformation only during OFDM symbols when the downlink data transmissionis permitted to begin.
 6. The method of claim 1, wherein the startlocations are different from a start location at which another UE is tomonitor for control information meant for that other UE.
 7. The methodof claim 4, wherein the first OFDM symbol includes both the controlinformation and some of the downlink data transmission.
 8. The method ofclaim 1, wherein the control information indicates that the downlinkdata transmission for the UE has been scheduled to begin at that startlocation.
 9. The method of claim 1, wherein the particular time intervalbegins at that start location.
 10. The method of claim 1, wherein thefirst and second start locations are adjacent start locations.
 11. Themethod of claim 1, wherein the control information is also receivedduring the particular time interval.
 12. The method of claim 11, whereinthe control information is in a first OFDM symbol of the particular timeinterval.
 13. A user equipment (UE) comprising: a receiver to receiveconfiguration signaling indicating first and second start locations,wherein the second start location occurs x OFDM symbols apart from thefirst start location; a control information processor to, for each oneof the start locations, monitor for control information at that startlocation, wherein the control information indicates whether a downlinkdata transmission for the UE has been scheduled during a particular timeinterval; the receiver to receive, for one of the start locations, thedownlink data transmission during the particular time interval.
 14. TheUE of claim 13, wherein each start location is at a respective OFDMsymbol.
 15. The UE of claim 13, wherein x=1.
 16. The UE of claim 13,wherein the particular time interval comprises one or more OFDM symbols,and wherein the control information is in a first OFDM symbol of the oneor more OFDM symbols.
 17. The UE of claim 13, wherein the controlinformation processor is to monitor for the control information onlyduring OFDM symbols when the downlink data transmission is permitted tobegin.
 18. The UE of claim 13, wherein the start locations are differentfrom a start location at which another UE is to monitor for controlinformation meant for that other UE.
 19. The UE of claim 16, wherein thefirst OFDM symbol includes both the control information and some of thedownlink data transmission.
 20. The UE of claim 13, wherein the controlinformation indicates that the downlink data transmission for the UE hasbeen scheduled to begin at that start location.